Solid-state thin film cells comprising layers of electrodes, electrolyte and current collectors are typically produced by first forming a stack comprising a first current collecting layer formed on a substrate, an electrode layer, an electrolyte layer, a second electrode layer and a second current collecting layer. The stack is then cut into separate sections to form individual cells. Each cell can then be coated with a protective layer in order to prevent passivation of the layers and possible shorts.
In order to form an electrical connection with the cell, for example in order to electrically connect current collectors of multiple cells stacked one on top of another, part of the protective layer is removed, for example by etching. Alternatively, a mask can be applied prior to the coating process to ensure that a portion of each current collector is left exposed. In each instance, the additional step of masking or etching adds complexity and cost the production process.